# Davis Line
## English

* 臺灣海峽中線

### Etymology

1950s, named after Brig. Gen. Benjamin O. Davis Jr. a United States Air Force (USAF) general and commander of the World War II Tuskegee Airmen who was commander of Air Task Force 13 (Provisional), Taipei, Taiwan (ROC).

### Proper noun

the Davis Line
* A boundary line, the centreline, the median line, in the middle of the Taiwan Strait, separating the (air) defence (control) zone of China from that of Taiwan.
** 1958 November 13, “Formosa ‘Battle Line’ Named After Gen. B. O. Davis”, in Jet‎, volume XV, number 2, Chicago: Johnson Publishing Company, →ISSN, →OCLC, Foreign News, page 17:The line beyond which American pilots do not fly in the troubled Formosa Strait area is called the “Davis Line” in honor of Brig. Gen. Benjamin O. Davis Jr., former commander of the 13th Provisional Air Force, stationed on Formosa[.] The mythical line is an undisclosed number of miles off the coast of Red China.
** 1966 December, M. H. Halperin, “The Prolonged Blockade: Reaction on Taiwan and in the Field”, in The 1958 Taiwan Straits Crisis: A Documented History‎, Santa Monica, Cali.: RAND Corporation, page 376:(3) Hostile aircraft may be considered to be committing hostile acts if flying east of "Davis Line" (an imaginary line running down the Taiwan Straits). (4) Unknown aircraft west of Davis Line will be intercepted, identified and kept under surveillance if hostile intent is suspected and may be engaged when declared by the Commander of ATF 13 (P) or any of his three designated subordinates as being hostile.
** 1988 December, Joseph Frederick Bouchard, “Naval Operations in Crises”, in Use of naval force in crises: A theory of stratified crisis interaction.‎, volume II, Stanford University, published 1989, →OCLC, page 453:The rules of engagement issued by Commander in Chief Pacific and U.S. Taiwan Defense Command for the air defense of Taiwan were highly restrictive prior to the 1958 crisis. American fighters on Taiwan were only permitted to fire on hostile aircraft entering Taiwan's airspace and were not permitted hot pursuit in international airspace. U.S. combat air patrols were required to remain east of the "Davis Line," which ran approximately down the center of the Taiwan Strait. After the crisis erupted, the U.S. Air Force commander on Taiwan convinced CINCPAC and the JCS that these rules would cripple air defense efforts in the event of concerted Communist air strikes against Taiwan. In September the JCS approved three relaxations to the rules of engagement: first, U.S. fighters were authorized to engage Communist aircraft crossing the Davis Line on an apparent course toward Taiwan or allied forces; […]
** 1991 June 27, “Crossing the Line”, in Far Eastern Economic Review‎, →ISSN, →OCLC, page 9, column 2:Peking may be testing a four-decade-old boundary in the Taiwan Strait after Taipei ended the "period of communist rebellion" in May. Military experts say China has deliberately crossed the boundary — called the Davis Line by the US 7th Fleet which once patrolled the strait — for only the second time since 1949.
** 2006, Bernard D. Cole, “Taiwan Air Force”, in Taiwan's Security: History and prospects‎, Routledge, →ISBN, →LCCN, →OCLC, page 112:The potential for in-flight encounters is increased by the constained geography between Taiwan and the mainland: the centerline of the Taiwan Strait usually has been honored as a "do not cross" boundary by both sides since it was delineated as the "Davis Line" by the US Formosa Strait Patrol in the 1950s.
** 2022 July 18, Courtney Donovan Smith [石東文], “Chinese intrusions in Taiwan's ADIZ, Ko Wen-je and death of the Davis Line”, in Taiwan News‎, archived from the original on 19 July 2022, Opinion‎:The Davis Line has surprisingly been in the news recently. Also referred to as the “median line,” “middle line” and “center line,” it refers to an imaginary air force “do not cross” line that runs right through the middle of the Taiwan Strait between Taiwan and China. […] Still, the PLAAF flouted the Davis Line sparingly, only crossing it on two more occasions in 2011 and 2019.
** 2022 September 7, Jesse Johnson, “'New normal' as Chinese warplanes push across Taiwan Strait median line”, in The Japan Times‎, archived from the original on 07 September 2022, Asia Pacific‎:The flights over the line — which China had rarely crossed in the past — have signaled a dramatic shift by Beijing. Prior to that, the Chinese military had ventured across the median line, which is also known as the center line or Davis Line, just four times between 1954 and August 2020 and only 23 times since September that year until Pelosi’s trip.
** For more quotations using this term, see Citations:Davis Line.

#### Usage notes

The Davis Line is more commonly referred to as the 'median line of the Taiwan Strait' or similar.

#### Translations
### Further reading

* Davis Line at the Google Books Ngram Viewer.